Use of decomposable polymer-coated submicron Cu particles with effective additive for production of highly conductive Cu films at low sintering temperature

Yong, Yingqiong; Nguyen, Mai Thanh; Yonezawa, Tetsu; Asano, Takashi; Matsubara, Masaki; Tsukamoto, Hiroki; Liao, Ying‐Chih; Zhang, Tengfei; Isobe, Shigehito; Nakagawa, Yuki

doi:10.1039/c6tc04360g

Cited by 27 publications

(15 citation statements)

References 41 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Because the radiation energy is absorbed from top of copper film, the temperature on the top surface of the sintered thin films are higher than that of the substrate. Because the substrate temperature only increase slightly (~20 °C) [28,29,30,31] after IPL treatment, there exists a temperature difference ~300 °C between the sintered copper film and the substrate. As the result, the large thermal expansion difference between the copper film and the substrate leads to serious crack formation.…”

Section: Resultsmentioning

confidence: 99%

“…In the literature, it has been found that cupric oxide coatings around copper nanoparticles can help particle connections in sintering process [14,27,28]. Moreover, a mixture of copper particles with various sizes are also found to be more efficient for particle fusion in the sintering process [29]. However, these experiments are performed in a nitrogen environment with a thermal sintering process.…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Sintering Copper Nanoparticles with Photonic Additive for Printed Conductive Patterns by Intense Pulsed Light

et al. 2019

View full text Add to dashboard Cite

In this study, an ink formulation was developed to prepare conductive copper thin films with compact structure by using intense pulsed light (IPL) sintering. To improve inter-particle connections in the sintering process, a cuprous oxide shell was synthesized over copper nanoparticles (CuNP). This cuprous oxide shell can be reduced by IPL with the presence of a reductant and fused to form connection between large copper particles. However, the thermal yield stress after strong IPL sintering resulted in cracks of conductive copper film. Thus, a multiple pulse sintering with an off time of 2 s was needed to reach a low resistivity of 10−5 Ω·cm. To increase the light absorption efficiency and to further decrease voids between CuNPs in the copper film, cupric oxide nanoparticles (CuONP) of 50 nm, were also added into ink. The results showed that these CuONPs can be reduced to copper with a single pulse IPL and fused with the surrounding CuNPs. With an optimal CuNP/CuONP weight ratio of 1/80, the copper film showed a lowest resistivity of 7 × 10−5 Ω·cm, ~25% conductivity of bulk copper, with a single sintering energy at 3.08 J/cm2. The ink can be printed on flexible substrates as conductive tracks and the resistance remained nearly the same after 10,000 bending cycles.

show abstract

Section: Resultsmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

Sintering Copper Nanoparticles with Photonic Additive for Printed Conductive Patterns by Intense Pulsed Light

et al. 2019

View full text Add to dashboard Cite

show abstract

“…Under the same experiment conditions (oven, sintering temperature and time, heating profile) and ink compositions, all samples can be considered having the same evaporation rate of IPA, thereby IPA evaporation rate is not the reason causing the significant difference in the resistivity of the sintered copper films. As reported for the sintering of copper particles/copper complex ink, the copper from the complex was generated and grew on the surface of added copper particles to form the final copper film2431. Low temperature sintering of copper particles without the metal complexes was also examined.…”

Section: Resultsmentioning

confidence: 99%

Effect of decomposition and organic residues on resistivity of copper films fabricated via low-temperature sintering of complex particle mixed dispersions

Yong

Nguyen

Tsukamoto

et al. 2017

Sci Rep

Self Cite

View full text Add to dashboard Cite

Mixtures of a copper complex and copper fine particles as copper-based metal-organic decomposition (MOD) dispersions have been demonstrated to be effective for low-temperature sintering of conductive copper film. However, the copper particle size effect on decomposition process of the dispersion during heating and the effect of organic residues on the resistivity have not been studied. In this study, the decomposition process of dispersions containing mixtures of a copper complex and copper particles with various sizes was studied. The effect of organic residues on the resistivity was also studied using thermogravimetric analysis. In addition, the choice of copper salts in the copper complex was also discussed. In this work, a low-resistivity sintered copper film (7 × 10−6 Ω·m) at a temperature as low as 100 °C was achieved without using any reductive gas.

show abstract

“…The lowest resistivity of 32 μΩ cm was achieved using 0.4-μm Cu particles at a sintering temperature of 120 °C for 30 min under an N 2 atmosphere. They also prepared Cu particles (154 ± 54 nm in size) protected with an amine-decomposable polymer (poly(propylenecarbonate), PPC) and mixed the PPC-protected Cu particles and CuF–AmIP complex to achieve a low resistivity at low-temperature sintering under an N 2 atmosphere [ 135 ]. PPC can be decomposed into smaller molecules via an aminolysis reaction with AmIP.…”

Section: Formulation Designs In Cu-based Mixed Inks/pastesmentioning

confidence: 99%

Surface and Interface Designs in Copper-Based Conductive Inks for Printed/Flexible Electronics

Tomotoshi

Kawasaki

2020

Nanomaterials

View full text Add to dashboard Cite

Silver (Ag), gold (Au), and copper (Cu) have been utilized as metals for fabricating metal-based inks/pastes for printed/flexible electronics. Among them, Cu is the most promising candidate for metal-based inks/pastes. Cu has high intrinsic electrical/thermal conductivity, which is more cost-effective and abundant, as compared to Ag. Moreover, the migration tendency of Cu is less than that of Ag. Thus, recently, Cu-based inks/pastes have gained increasing attention as conductive inks/pastes for printed/flexible electronics. However, the disadvantages of Cu-based inks/pastes are their instability against oxidation under an ambient condition and tendency to form insulating layers of Cu oxide, such as cuprous oxide (Cu2O) and cupric oxide (CuO). The formation of the Cu oxidation causes a low conductivity in sintered Cu films and interferes with the sintering of Cu particles. In this review, we summarize the surface and interface designs for Cu-based conductive inks/pastes, in which the strategies for the oxidation resistance of Cu and low-temperature sintering are applied to produce highly conductive Cu patterns/electrodes on flexible substrates. First, we classify the Cu-based inks/pastes and briefly describe the surface oxidation behaviors of Cu. Next, we describe various surface control approaches for Cu-based inks/pastes to achieve both the oxidation resistance and low-temperature sintering to produce highly conductive Cu patterns/electrodes on flexible substrates. These surface control approaches include surface designs by polymers, small ligands, core-shell structures, and surface activation. Recently developed Cu-based mixed inks/pastes are also described, and the synergy effect in the mixed inks/pastes offers improved performances compared with the single use of each component. Finally, we offer our perspectives on Cu-based inks/pastes for future efforts.

show abstract

Use of decomposable polymer-coated submicron Cu particles with effective additive for production of highly conductive Cu films at low sintering temperature

Cited by 27 publications

References 41 publications

Sintering Copper Nanoparticles with Photonic Additive for Printed Conductive Patterns by Intense Pulsed Light

Sintering Copper Nanoparticles with Photonic Additive for Printed Conductive Patterns by Intense Pulsed Light

Effect of decomposition and organic residues on resistivity of copper films fabricated via low-temperature sintering of complex particle mixed dispersions

Surface and Interface Designs in Copper-Based Conductive Inks for Printed/Flexible Electronics

Contact Info

Product

Resources

About